"Every day on Twitter, someone would say, 'How can you not have this? Where is Nosferatu?'

"I would tiresomely reply, 'If I included everything, it would be just me sitting in a chair going… and then The Abominable Dr Phibes happened'."

The writer - who starred in Doctor Who in 2007 - added: "Doctor Who fans exist for the minutiae. They'll complain about everything. They'll probably complain about Verity Lambert's shoes. But I made it for everybody and I hope it's very touching."